Liquid metering apparatus



Aug. 25, 1953 R. DUNAVANT LIQUID METERING APPARATUS 5 Sheets-Sheet 1 Filed Jan. 29 1951 INVENTOR. [PE 2. DUA/A VANT A 7'TOFNEY5 25, 1953 1.. R. DUNAVANT 2,649,713

LIQUID METERING APPARATUS 3 Sheets-Sheet 3 Filed Jan. 29, 1951 2a 5o if" /6"' z 4 60 t 76 64 INVENTOR.

[5 E. DuA/AvAA/T Patented Aug. 25, 1953 UNITED STATES PATENT OFFICE LIQUID METERING APPARATUS Lee R. Dunavant, Seattle, Wash.

Application January 29, 1951, Serial No. 208,379

7 Claims. 1

This invention relates to apparatus for metering flow of liquids and is primarily concerned with a, practicable fuel oil distribution system involving piping of the fuel oil directly from a master reservoir to any desired number of individua1 consumers, whose use of the oil is to be separately metered as a basis for compensation to the distributor. The principal problem which arises in any such system and one which evidently has prevented its workability or use in the past, is that of providing a satisfactory metering device for registering th quantity of fuel oil used by individual consumers, such as would satisfy the requisite standards of fire insurance underwriters, builders, investors, and finally the fuel oil distributor and individual paying consumers.

The customary practice has been for the distributor of fuel oil to maintain one or more delivery trucks which carry the fuel oil either from the distributors own storage facilities or from a wholesale storage station to the various consumer locations. Because of the necessity of frequent trips a considerable part of the cost to the consumer is attributable directly to the distributors delivery cost. This may be reduced somewhat by the installation of a consumer storage tank of large capacity, so that fewer delivery trips are necessary, but any such reduction is considerably offset by the cost of the larger storage tank. Another difficulty with the customary method of fuel oil distribution is the necessity, especially in winter months, of frequent inspections of fuel on hand to avoid running out of oil. Sometimes through forgetfulness a tank may go empty unnoticed.

The present invention in one aspect is directed to a workable fuel oil distribution system or the like, by which oil is piped directly from a central or common storage station of large capacity to individual consumers spread over a substantial area, who then pay on the basis of the reading of a metering device installed in their homes or other convenient location. More specifically, an object is to provide in such a system a meterin device capable of registering with reliable high accuracy the total quantity of fuel oil received by'a consumer, irrespective of such adverse operating conditions as rate of consumption by the furnace or other consuming apparatus, oil pressure in the line, and varying conditions of an ambient nature, such as temperature, humidity, vibrations, etc.

A more specific object of the invention is a durable, rugged and relatively inexpensive liquid metering apparatus which is inherently more accurate and reliable than any previously known apparatus of the same general type, and is so constituted that it may be manufactured on a mass production basis without being critically dependent for its accuracy of operation upon manufacturing tolerances, and the like.

Such apparatus is generally of the type in which a local container of known volume arranged to receive liquid and dispense it to a local consuming device is automatically refilled whenever the level of liquid in such container drops below a certain critica1 point, the number of refills being automatically registered in a meter or counter as an indication of total quantity of liquid dispensed. The chief problem which arises in obtaining sufficient accuracy with that type of metering device is one of actuating its refill and discharge control valves for initiating and terminating each refill operation at the respective instants of time in which the container contents reach the correct minimum and maximum volume levels. Manufacturing tolerances, vibrations, temperature effects, pressure, etc., which normally influence the accuracy of such devices have largely been overcome as sources of error in the present apparatus as hereinafter described.

With the foregoing considerations in view, and others as will hereinafter appear, the present invention is illustrated in its application to a liquid fuel distribution system of the type mentioned.

The principal features of the invention reside in the novel valve mechanism controlling refilling and emptying of the local metering container,

and in the coacting float apparatus which, in

cooperation with container means, responds with unusual sensitivity to correct maximum and minimum liquid contents volume in the container to provide the necessary impetus for actuating such valve mechanism and thereby terminate and initiate refill operations automatically.

More specifically, the improved control valve mechanism comprises shiftable means preferably comprising a first rocker element operatively connected to the container input and output control valves and urged to remain in either of extreme limit positions by yieldable overcentering spring means. A second shiftable means, again preferably another rocker element, likewise having overcentering spring means urging it to remain in either of opposite limit positions, is moved, alternately, past the overcentering point of its spring means in one direction by the float mechanism when refilling of the local metering container is to be initiated, and oppositely past the over- 3 center point of its spring means when a refilling operation is to be terminated. A lost-motion coupling arrangement including abutment elements coacting between, or forming parts of the two rockers permits the second, or, rocker to be moved the full distance from one limit position to a point materially past the overcentering point of its spring means without causing any movement of the first or valve-connected rocker element out of its then-established limit position. Immediately thereafter, however, the second rocker element is driven by its overcentering spring means the remaining distance to its opposite limit position and thereby abruptly snaps the first rocker element past the overcentering point of its spring means and causes it to reverse the positions of the input and output valves. Such valve reversing action following the lost-motion interval of the second rocker begins and ends in a short instant of time,-

and thereby greatly increases the accuracy of the metering apparatus. The chief reason it accomplishes this is that it eliminates the indeterminate delay period of former devices in which one valve is slowly moving to open position while the other slowly moves to closed position, during which period liquid begins to leave the container while more liquid begins to enter it, the quantities thereof being undeterminedand unregistrable on the meter or counter device because they vary with rate of fuel consumption as well as fuel line pressure.

Sensitive actuation of the valve-connected rocker precisely at the respective instants in which volume of liquid in the metering container reaches minimum and maximum metering values, for refill and cut-off, respectively, is achieved by providing a container means including a main storage space of relatively large capacity and upper and lower float-receiving passages of relatively small cross section which extend upwardly from the top level of the main storage space and downwardly from its bottom level, respectively. The float-actuated rocker element receives its control impetus to initiate and terminate refilling operations as the level of liquid, hence the float, moves predetermined distances into the lower and upper of such passages, respectively. Because the liquid-containing net cross section of the upper and lower liquid passages, especially as reduced by entrance of the float, is much smaller than that of the main storage space of the container means, the final travel of the fioat into eitherof'its extreme'positions is greatly accelerated for a given rate of delivery or discharge of liquid from the container as a whole whereby any slight variations or deviations in the actual control positions of the float can have no appreciable effecton the metered content volume of the container 'means as registered on a counter mechanism which indicates number of refills of the container.

These and other features, objects and advantages of the invention, including details of construction of the preferred and illustrated metering apparatus, will now be'described more fully by reference to the accompanying drawings.

Figure 1 is a simplified plan view illustrating a typical system layout for distribution of fuel oil from a central storage reservoir to individual consumer dwelling units or the like.

Figure 2 is a sectional side view of the improved metering apparatus in its preferred form, as applied in such a-system.

Figure 3 is a fractional view similar to Figure 2, but showing the control valve mechanism in a different operating position.

Figure 4 is a perspective view of the control valve mechanism and immediately associated parts of the apparatus.

Figure 5 is a sectional side view of a drain cock for removing any condensation water or oil from the container bottom.

Figure 6 is a side elevation, partly in section, of safety cut-off valvemechanism operated by overflow from the localcontainer' means.

Figure 7 is a side elevation view of modified metering apparatus corresponding in purpose and operation to; that appearing in Figure 2.

In Figure 1 the system arrangement is simply that of a central storage tank H), from which fuel oil is piped to. two or more individual consumer dwelling units l2' 'or other consumer locations through main conduits and local or branch conduits [6. In each branch conduit 16, preferably at or inside each dwelling unit is located a metering device 18., by which the distributor and individual consumer alike are informed of the total amount of oil which has flowed through the local branch conduit.

The novel liquid metering apparatus enabling such a system to be used for fuel oil delivery, and having other possible uses is shown in its preferred form in Figures 2 to '6,.inclusive.

The metering apparatus container includes a hollow spherical ball 20 of perhaps five gallons approximate capacity :and which constitutes the containers .main storage chamber for liquid entering therein through the input conduit 16. .An opening in the top of the spherical chamber 29 leads upwardlyinto a vertical extension tube 22 of relatively small liquid-containing cross section. A similar opening in. the .bottom'oi such chamber leads downwardly into. a second vertical tubular extension 2-2. A generally rectangular control valve housing 25 adjoining the lower extension 24 has an end cover. 23 through which the input and output conduits l6 and 30, respec tively, communicate with the interior of the composite containermeans including the container portions 20, 22, ill-and 28; The bottom of lower extension 2 is closed off by the plate 32 which in the, illustrated. construction constitutes the top of a box-like compartmented chamber 3 functioning as the metering apparatus support. A partition 36 divides this chamber into a safety cut-off ,valve housing'compartment Sta, and an oil accumulator compartment 3%. The latter provides an auxiliaryoil storage space of substantial capacity interposed in'the outputconduit 38 leading from the metering container 283 etseq. to the oil furnace or-other consuming apparatus (not shown).

Outflow of oil from themetering container into the conduit 30 must pass, through a selectively actuated output cut-off valve 38, while inflow from input conduit 16 into themetering container must pass through the selectively actuated input cut-off valve-dfi as'shown. The level of liquid in the lower tubular extension 24 is never allowed to fallbelow the levelof the out put cut-off valve 38 so-that when this valve is open oil will drain constantly from the metering container 20 6t seq. :intothe output line 33 and accumulator-36, while oil is being consumed, or there is still receiving-space in the accumulator. A vent tube 42 extending from the top :of the accumulator space opens into a side compartment 44 'adjo'ining theztop 0f .the upper extension 22..

"The function of the accumulator is-to provide a supply of fuel oil to the furnace or other consuming apparatus in the'consumers establishment during the intermittent periods when outflow valve 38 is closed and inflow valve 40 is opened, and the metering container including the main storage chamber 29 is being refilled from the input conduit I6. Unless the outflow valve 38 were fully closed throughout such refilling operations, more fuel oil might actually enter the container means through the input conduit l6 than the actual calibrated capacity of the container as a measuring device, as the furnace or other consuming apparatus, or the accumulator itself, might draw fuel through the line 3|] during such refilling periods of the metering container. A counter mechanism 46 mounted on the cover 48 and actuated with each refilling operation of the metering container as later explained will then indicate total volume of fuel oil received through the input conduit l 6 over a period of time, as desired.

Referring particularly to Figure 4, the inflow and outflow cut-off valves 38 and 40 are of conventional needle valve construction, having reciprocable control plungers 38a and 40a, respectively. In the figure maximum withdrawal of a valve plunger from the valve casing corresponds to the valves open position, whereas maximum entry of the plunger into such casing corresponds to the valves closed position. The valves 38 and 40 are mounted on the cover plate 28 in positions of vertical alignment, extending horizontally inward from such cover plate generally toward the vertical axis of the metering container portions 20, 22 and 24.

The needle-valve plungers 38a and 40a are connected for simultaneous actuation in mutually opposite directions by a rocker member 50. This rocker, having generally vertical arms, the ends .1

of which are pivotally connected to the valve plungers 38a and 40a by coupling links 52 and 54, respectively, is pivotally supported by the end of a post 56, mounted on the cover plate 28 intermediate the valves 38 and 40, such that the rocker pivots in the general plane common to the two needle valves. The rocker has a control arm 50a projecting generally at right angles from its valve-connected arms and terminating in a double fork. Near its forked outer or swinging end the control arm 58 carries a central anchor pin 58 which extends through the arm and outwardly from its opposite sides to serve as an anchor for corresponding ends of two overcentering springs 60, whose respective opposite ends are secured to lugs 62 fixed to the cover plate 28. The lugs 62, located adjacent the base of the mounting post 56, lie along a line at right angles to the general plane common to the valves 38 and 40. Thus since the rocker 50 is of symmetrical form and the anchor pin is located on its central axis, the.

overcentering point of the'springs 60 in terms of rocker position corresponds to the horizontal position of the rocker control arm, in which it is generally aligned with the longitudinal axis of the mounting post 56. In this intermediate position of the rocker the valve plungers 38a and 40a lie approximately midway between their open and closed positions. When the rocker is moved past the overcentering point of the springs 60 in either direction, they will of course urge it the remaining distance to the nearest limit position of the rocker, closing one of the needle valves and opening the other simultaneously thereby.

The mechanism for actuating the. rocker 50.

6 for movement from either extreme position past the overcentering point ofits springs 60 includes a second rocker 64., The latter is composed of side members 64a pivotally supported by the ends of mounting posts 66 and a cross bar member 641) interconnecting the swinging ends of the side members and extending transversely through the space between tines of the forked end of. the first rockers control arm 50a. The posts 66 are mounted on the cover plate 28 in the line of the central post 56 and spring anchor lugs 62, the pivot axis of the rocker 64 preferably coinciding with that of the rocker 50 as shown. The overcentering springs 68 for the second rocker 64 are connected between the cross bar member 641) and respective anchor lugs 10 carried by the cover plate 23 at respective locations beside the posts 66. These anchor lugs are likewise located on the base line of the three posts.

Thus the-arrangement of the second rocker 64 with relation to its overcentering springs 68 is such that the springs overcentering point corresponds to the intermediate position of the second rocker, in which it lies generally in the plane containing the two mounting posts 66. When the rocker is moved to either side of this intermediate position it is abruptly swung by its springs the remaining or final distance to the intended limit position of such rocker.

The important feature of the two rockers and overcentering spring combination is that the force of the springs 68 to effect such final movement of the rocker 64 is sufliciently great relative to the forceof the springs 60 tending to'retain rocker 56 in its established limit position, that the rocker bar 64b upon striking a tine of the forked control'arrn 50:]. carries the rocker 50 from its established limit position and past the overcentering point of its springs 60, whereupon the rocker 5!! moves the remaining distance to its opposite limit under the combined force of its own springs as well as those of the rocker 64 as the latter completes its final movement. The latters limit positions is established preferably by the rocker 5G in its respective limit positions, whereby the springs of both rockers normally cooperate to hold one or the other of the needle valves closed tightly.

In the immediately foregoing it will be noted that before the cross bar 64b contacts the control arrn tine of the rocker 50 to shift the latter from one limit position to another, the rocker 64 must first swing the width of the space between tines of control arm 50a. Insofar as the rocker 50 is concerned, this initial movement of the rocker 66b is lost motion, commencing with initiation of movement of the rocker 64 from its initial limit position and extending through swinging of such rocker to a point materially past its intermediate position, so that when the crossbar member 64b does strike the tine of the control arm 50a it already has considerable velocity imparted by its overcentering springs 68. As a result its impact with the tine drives the rocker 56 instantly from its established limit position past its intermediate position for abrupt movement to the opposite limit position thereof.

In order to swing the rocker 64' back and forth intermittently between limit positions as described and thereby reverse the positions of the needle valves 38, 40 automatically in the operation of the metering apparatus, the rocker 64 also has a control arm 64c terminating in a yoke or fork 64d.

Referring to Figure 2, a float 12 of annular form is f ree to rise and 'fall on a vertical float guide tube 14 with changing level of liquid in the metering container 23 et seq. The guide tube 14 in turn encircles and slides vertically on a vertical rod 16. The rod, extending along the common central axis of the tubular extensions 22 and 25, is fixedly Supported at its upper end by the cover plate 43 and at its lower end by being threaded into a socket in the top of a drain cock housing 18 in the base of the lower extension 24. The rocker for-k 64d embraces the lower portion of slide tube M although it does not necessarily contact the same-as shown in Figure 4. An annular flange Ma. on the lower end of this tube normally rests on the top of the drain cock housing it (Figure 2). A flanged collar 80 fixed on the slide tube at a location materially above the base of the upper extension tube 22 is engaged by the top of the float l4 when the latter rises into such extension after the main storage chamber 20 is filled with liquid. Further ascent of the float into the passage 22 progressively raises the slide tube M, hence the flange Ma to engage the fork G id and swing the rocker 64 upward. Finally, the rocker 64 passes the overcentering point of its springs and snaps abruptly the remaining distance to its opposite limit position, carrying with it the rockers 50, to close the valve 40 and open the valve 33 (Figure 3).

Then as liquid drains from the metering container, the float l2 gradually descends. A tubular extension 82, projecting downward from the bottom of the float-,has an annular collar 82a. When the float finally descends into the lower tubular passage 25, this collar approaches the fork 63d of rocker $4 inits' upswung position as shown Figure 3. As the float continues to descend and the flange 32a engages the fork, the rocker S4 is swung progressively downward (Figure 4) until it again reaches the overcentering point of its springs fifi, which thereupon swing it the remaining distance to its lower position, carg the rocker 59 past its intermediate position by and again reversing the valves (Figure 2). s the float havin'g extens'ion flange 82:; causes award swinging of the rockers 50 and 54' when the float reaches its lowermost limit of travel, whereas the slide rod flange Ma causes upward swinging of the rockers when the float reaches its uppermost limit of travel, corresponding respectively to the minimum and maximum liquid volume content of the metering container 29' et seq.

An annular flange Nib on the upper end of the slide tube 14 normally rests upon the forked end of an arm 84', which is pivoted at 85 on the lower end of a supporting post 88 depending from the cover plate 48-. The weight of the slide tube 5 3 is suiiicient to hold the arm 8:! down against the upward force exerted on it by the spring 98 connected between the arm and an offset portion sea of the post 88. A counteractuating plunger #Ba, having a slot and pin connection 92 to the arm 84, is then in its lowermost position". When the float l2 approaches its uppermost position of travel in the tubular passage 22 and begins to raise the slide tube i4 by engagement of the collar 82, the spring 99 is then permitted to raise the arm 86 progressively. This raises the counter plunger 46a and finally actu-atesthe counter 46 to register on its indicator thecompletion of another refill of the metering container. This it does just before the float 12 actually reaches its upper- 8 most position of travel to reverse the valves 38 and 40 and terminate the refilling operation.

It will be noted in Figures 2 and 3 that the net liquid-containing cross Section of the tubular passages 28 receiving the float is a negligible fraction of the general or average cross section of the main storage chamber 20, when the float enters the respective passages by rise or fall of liquid level into the same. This feature of the metering apparatus greatly adds to its precision and largely overcomes any of the usual sources of error, such as manufacturing tolerances, etc, because of the fact that the upper and lower control positions of the float for actuating the valve mechanism are not critical. If, for example, the actual upper control position of the float should deviate somewhat from the theoretical or intended position thereof, whether above or below the latter, the resultant difference between the maximum content volume of liquid metered into the container from the theoretical or intended amount will only be equal to the negligible quantity representing the product of such positional deviation and the net liquid-containing cross section of the tubular passage 22. The same is true with respect to the effect of deviation of the lower float control position from the theoretical or intended position thereof, and any resultant deviation of the minimum content volume of liquid in the container from the theoretical or intended amount is likewise negligible. Consequently the calibrated refill capacity of the metering container (26, 22, as and 25') will be virtually unaffected by moderate variations in the control positions of the float, whatever their cause, as long as the range of deviation does not shift the actual liquid levels at the control point out of the passage 22 or 24, respectively.

It will be noted that the rate of rise or descent of liquid level in the metering container greatly accelerates upon entering the respective upper and lower tubular passages 22 and 24 under given conditions of supply or dispensing of liquid. The float 72, therefore, likewise experiences the same acceleration when it approaches its extreme positions of travel. Consequently the float is normally moving at a comparatively rapid rate when it actuates the control valve mechanism, and completion of the control movement of the rocker 54 to actuate the valve-eonnected rocker 53 occurs with corresponding rapidity. Because the rocker 64 reverses the position of the rocker 50' immediately after the rocker 64 passes its over-centering position in either direction the positions of the needle valves 38 and 43 are abruptly reversed almost simultaneously with arrival of the float at its respective control positions. Thus as previously mentioned the valve mechanism, including the lost-motion coupling between the two springurged rockers, and the special float mechanism incorporating the reduced extension portions 22 and 24, cooperate to produce a highly accurate metering device which registers on the counter 46 the total volume of liquid entering the container through the input conduit (6 over a period of time.

The drain cook 94, actuated by rotation of its faceted end with a wrench or other tool, is received in the housing 78 having port openings 78a at the bottom of the metering container. The function of this valve is to permit draining off any Water of condensation which may have collected in the bottom of the container over a period of time, so that the water level in the container bottom will never be permitted to rise '9 as high as the valve38, for example. The needle valve housing 26 hasa sloping bottom 26a rather than a horizontal bottom locatedjust below the valve 38, sothat any water of condensation will run down to the bottom of the container tube 24 and will not collect jin'j the vicinity of the needle valves whereit might freeze in winter weather and cause the valves to stick.

As optional safety equipment, "the apparatus includes a special cut-off valv 96 located in the input conduit I6 and operable to block flow of liquid into the container should the latter for any reason overflow at the top. If the level of liquid rises in the upper extension passage 22 to a point above the'bottom of the side compartment 44, the liquid will immediately run down the inside of the drain pipe 98 and fill a counterweight cup Hill (Figure). The latter is carried 'by a pivoted arm I02 normally held in upraised position by a spring "34; However, when the counterweight cup fills with overflow liquid it swings downward against the force of the spring I04 and actuates the cut-off valve plunger I06 to mov the valve element I98 to its seat against the port H0, and therebycut off inflow of liquid through the conduit Hi to the metering apparatus container. The action of this valve mechanism is illustrated in Figure 6, wherein the solid line position of the components represents the overflow operating condition and the dotted line position thereof represents the normal operating condition.

A modified metering apparatus container arrangement appears in Figure '7. In this case the main storage chamber 20'- is physically separate from the float passage, and the latter constitutes a continuous straight tube 2'Z 24' of the same cross section as thetubularextensions 22 and 24 in the previous form. The top of-the chamber 20' is connected by a vent pipe 20'a to the top of the tube 22', 24' while'the bottom of the reservoir 29' communicates with the float tube through a short lateral pipe 20b.' The bottom of the latter is located at a level designated by the broken line A, which is above the lowermost level of liquid in-the float tube in the lower extreme or control position of the-float-lz'therein. Likewise, the top of the chamber 20} is at the level of the broken line B, which is below the highest level of liquid in the float tube corresponding to the upper or opposite control position of the float. Consequently; with the controlmechanism otherwise similar to that in the previously described form, this modified form of metering apparatus possessed substantially the same degree of accuracy and operates in the same manner as that already described, it being understood that the net liquid-containing cross section of the float tube 22', 24' around the float is negligible relative to that of the main storage chamber 20'.

I claim as my invention:

1. Liquid metering apparatus comprising a liquid container having therein a main storage space for liquid, inlet and outlet passages and valves to fill and drain liquid from said container, mutually aligned means forming container end spaces extending respectively above and below the maximum and minimum levels of liquid contained in said main storage space-and having a materially smaller liquid-containing cross section than said storage space, a guide rod extending between and through said aligned end spaces, an elongated sleeve slidably received on said rod to extend between and at least partially through said aligned end spaces, a float slidably received on said sleeve sleeve for operating said valve control mechanism in one sense by longitudinal shifting of said sleeve, means on the opposite end of said sleeve to be engaged by the float for. effecting such shifting as such float enters the corresponding opposite container end space along said sleeve, and means on the float for operating said valve control mechanism in the reverse sense by movement of the float into the first passage along said sleeve.

2. The apparatus defined in claim 1, wherein the valve control mechanism comprises a rocker element pivoted about an axis transverse to the sleeve and having a forked end embracing the sleeve for movement therealong and positioned for engagement by the sleeve abutment means during longitudinal shifting of the sleeve in one direction and by the float during movement of the float in the opposite direction along the sleeve.

3. The apparatus defined in claim 2, wherein the rocker element has an over-centering spring connected thereto urging the same into either of opposite limit positions, and the valve control mechanism further comprises a second rocker element having oppositely extending arms actuatingly connected to the respective valves, means pivoting the second rocker element intermediate said arms about an axis substantially coincident with the first rocker elements axis, and overcentering spring means urging said second rocker element into either of opposite valve-actuated limit positions, one of said rocker elements having an operating element and, the other of said rocker arms having a pair of operating elements straddling said first operating element with material clearance therebetween, permitting initial lost motion of the first rocker element relative to the second during swinging of the first rocker element in either direction to effect movement of said second rocker element into the corresponding limit position thereof.

' 4. Liquid metering apparatus comprising liquid container means including therein a main storage space for liquid, liquid input means to deliver liquid into said container means and fill said main storage space therein, liquid output means to deliver liquid from said container means and empty said main storage space, a float, means extending beyond the top and bottom levels of the main storage space guiding said float along an established path within said liquid container means to rise and fall with the level of liquid therein throughout the full variation thereof in said main storage space, said liquid container means also including a float-receiving liquid passage extending along said float path above the highest level of liquid in said main storage space, and a corresponding float-receiving liquid passage extending along said float path below the lowest level of liquid in said main storage space, each of said liquid passages being of a liquid-containing cross section which is generally small in relation to that of said storage space, whereby during constant rate of delivery of liquid to said container means the level of liquid therein, hence of said float, will rise into said upwardly extending passage and at a materially accelerated rate, after said main storage space is filled thereby, and during constant rate of discharge of liquid from said container means the level of liquid therein, hence said float, will fall into said downwardly extending tube passage and at a materially accelerated rate, after said main storage space is emptied thereby, and snapaction inlet and outlet metering valve means actuated by said float upon predetermined travel thereof upwardly into said upwardly extending passage for cutting 01? flow of liquid into the container and simultaneously opening the outlet thereof, and by said float upon predetermined travel thereof downwardly into said downwardly extending passage for simultaneously reversing said inlet and outlet valves, respectively.

5. Apparatus defined in claim 4, wherein the metering valve means comprises input and output cut-oh valves cooperating with the liquid input and output means, respectively, shiftable valve operating means operatively connected to said valves to close either thereof and simultaneously open the other by shifting of said valve operating means in one direction or the other between opposite limit positions, respectively, overcentering spring means acting on said shiftable valve operating means and urging the same into either limit position thereof when shifted toward such limit position through an intermediate position thereof corresponding to the overcentering point of said spring means, lost-motion shiftable control means for actuating said shiftable valve operating means and including a shifting control element guided for movement between opposite limit positions through an intermediate position thereof, and operable to engage and thereby shift said valve operating means from either limit position thereof through its intermediate position during movement of said control means shifting element from a position materially past its intermediate position to the corresponding nearest limit position of such control means element, respectively, means movable by the float and in turn moving said control means element from one limit position thereof past its intermediate position upon the predetermined upward travel of such float, means movable by the float and in turn moving such control means element from its opposite limit position past its intermediate position upon the predetermined downward travel of such float, and additional overcentering spring means acting on said control means element and urging the same into either of its limit positions when moved toward 12 h same past its intermediate p sition, thereby correspondin ly shifting said ,shiftable valve operating means abruptly from one limit position past theovercentering point of its spring means, and thus .into its opposite limit position by action of such latter spring means.

6. Apparatus defined .claim 6, wherein the valves are positioned side by .side and the shiftable valve roperating means comprises a first rocker member having oppositely extending arms .actuatingly connected to the respective valves and means supporting such rocker member intermediate said arms to pivot about an axis transverse to a line extending between said valves, the lost-motion shi-ftable control means comprising a second rocker member pivoted about an axis substantially coincident 'with that of said first rocker member, as-the control means shifting element, and lost-motion coupling means coacting between said first and second rocker members and including a set of abutment elements movable With the second rocker member and a cooperating set of abutment elements movable with the first rocker member, the first set being movable freely in relation to the cooperating set during movement of the second rocker member from either limit position thereof to the position materially past its intermediate position, respective ly, and conjointly with such cooperating set during remaining movement of the second rocker member to the opposite limit position thereof.

7. Apparatus defined in claim 6, wherein one abutment element set comprises spaced arms carried by one rocker member and the other abutment element set is formed by opposite sides of a striker element carried by the other rocker member and movable across the space between such arms to engage either thereof for movement of the rocker member carrying such arms thereby.

LEE R. DUNAVANT.

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